efi.c 21 KB

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  1. /************************************************************
  2. * EFI GUID Partition Table handling
  3. *
  4. * http://www.uefi.org/specs/
  5. * http://www.intel.com/technology/efi/
  6. *
  7. * efi.[ch] by Matt Domsch <Matt_Domsch@dell.com>
  8. * Copyright 2000,2001,2002,2004 Dell Inc.
  9. *
  10. * This program is free software; you can redistribute it and/or modify
  11. * it under the terms of the GNU General Public License as published by
  12. * the Free Software Foundation; either version 2 of the License, or
  13. * (at your option) any later version.
  14. *
  15. * This program is distributed in the hope that it will be useful,
  16. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  18. * GNU General Public License for more details.
  19. *
  20. * You should have received a copy of the GNU General Public License
  21. * along with this program; if not, write to the Free Software
  22. * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  23. *
  24. *
  25. * TODO:
  26. *
  27. * Changelog:
  28. * Mon Nov 09 2004 Matt Domsch <Matt_Domsch@dell.com>
  29. * - test for valid PMBR and valid PGPT before ever reading
  30. * AGPT, allow override with 'gpt' kernel command line option.
  31. * - check for first/last_usable_lba outside of size of disk
  32. *
  33. * Tue Mar 26 2002 Matt Domsch <Matt_Domsch@dell.com>
  34. * - Ported to 2.5.7-pre1 and 2.5.7-dj2
  35. * - Applied patch to avoid fault in alternate header handling
  36. * - cleaned up find_valid_gpt
  37. * - On-disk structure and copy in memory is *always* LE now -
  38. * swab fields as needed
  39. * - remove print_gpt_header()
  40. * - only use first max_p partition entries, to keep the kernel minor number
  41. * and partition numbers tied.
  42. *
  43. * Mon Feb 04 2002 Matt Domsch <Matt_Domsch@dell.com>
  44. * - Removed __PRIPTR_PREFIX - not being used
  45. *
  46. * Mon Jan 14 2002 Matt Domsch <Matt_Domsch@dell.com>
  47. * - Ported to 2.5.2-pre11 + library crc32 patch Linus applied
  48. *
  49. * Thu Dec 6 2001 Matt Domsch <Matt_Domsch@dell.com>
  50. * - Added compare_gpts().
  51. * - moved le_efi_guid_to_cpus() back into this file. GPT is the only
  52. * thing that keeps EFI GUIDs on disk.
  53. * - Changed gpt structure names and members to be simpler and more Linux-like.
  54. *
  55. * Wed Oct 17 2001 Matt Domsch <Matt_Domsch@dell.com>
  56. * - Removed CONFIG_DEVFS_VOLUMES_UUID code entirely per Martin Wilck
  57. *
  58. * Wed Oct 10 2001 Matt Domsch <Matt_Domsch@dell.com>
  59. * - Changed function comments to DocBook style per Andreas Dilger suggestion.
  60. *
  61. * Mon Oct 08 2001 Matt Domsch <Matt_Domsch@dell.com>
  62. * - Change read_lba() to use the page cache per Al Viro's work.
  63. * - print u64s properly on all architectures
  64. * - fixed debug_printk(), now Dprintk()
  65. *
  66. * Mon Oct 01 2001 Matt Domsch <Matt_Domsch@dell.com>
  67. * - Style cleanups
  68. * - made most functions static
  69. * - Endianness addition
  70. * - remove test for second alternate header, as it's not per spec,
  71. * and is unnecessary. There's now a method to read/write the last
  72. * sector of an odd-sized disk from user space. No tools have ever
  73. * been released which used this code, so it's effectively dead.
  74. * - Per Asit Mallick of Intel, added a test for a valid PMBR.
  75. * - Added kernel command line option 'gpt' to override valid PMBR test.
  76. *
  77. * Wed Jun 6 2001 Martin Wilck <Martin.Wilck@Fujitsu-Siemens.com>
  78. * - added devfs volume UUID support (/dev/volumes/uuids) for
  79. * mounting file systems by the partition GUID.
  80. *
  81. * Tue Dec 5 2000 Matt Domsch <Matt_Domsch@dell.com>
  82. * - Moved crc32() to linux/lib, added efi_crc32().
  83. *
  84. * Thu Nov 30 2000 Matt Domsch <Matt_Domsch@dell.com>
  85. * - Replaced Intel's CRC32 function with an equivalent
  86. * non-license-restricted version.
  87. *
  88. * Wed Oct 25 2000 Matt Domsch <Matt_Domsch@dell.com>
  89. * - Fixed the last_lba() call to return the proper last block
  90. *
  91. * Thu Oct 12 2000 Matt Domsch <Matt_Domsch@dell.com>
  92. * - Thanks to Andries Brouwer for his debugging assistance.
  93. * - Code works, detects all the partitions.
  94. *
  95. ************************************************************/
  96. #include <linux/crc32.h>
  97. #include <linux/ctype.h>
  98. #include <linux/math64.h>
  99. #include <linux/slab.h>
  100. #include "check.h"
  101. #include "efi.h"
  102. /* This allows a kernel command line option 'gpt' to override
  103. * the test for invalid PMBR. Not __initdata because reloading
  104. * the partition tables happens after init too.
  105. */
  106. static int force_gpt;
  107. static int __init
  108. force_gpt_fn(char *str)
  109. {
  110. force_gpt = 1;
  111. return 1;
  112. }
  113. __setup("gpt", force_gpt_fn);
  114. /**
  115. * efi_crc32() - EFI version of crc32 function
  116. * @buf: buffer to calculate crc32 of
  117. * @len - length of buf
  118. *
  119. * Description: Returns EFI-style CRC32 value for @buf
  120. *
  121. * This function uses the little endian Ethernet polynomial
  122. * but seeds the function with ~0, and xor's with ~0 at the end.
  123. * Note, the EFI Specification, v1.02, has a reference to
  124. * Dr. Dobbs Journal, May 1994 (actually it's in May 1992).
  125. */
  126. static inline u32
  127. efi_crc32(const void *buf, unsigned long len)
  128. {
  129. return (crc32(~0L, buf, len) ^ ~0L);
  130. }
  131. /**
  132. * last_lba(): return number of last logical block of device
  133. * @bdev: block device
  134. *
  135. * Description: Returns last LBA value on success, 0 on error.
  136. * This is stored (by sd and ide-geometry) in
  137. * the part[0] entry for this disk, and is the number of
  138. * physical sectors available on the disk.
  139. */
  140. static u64 last_lba(struct block_device *bdev)
  141. {
  142. if (!bdev || !bdev->bd_inode)
  143. return 0;
  144. return div_u64(bdev->bd_inode->i_size,
  145. bdev_logical_block_size(bdev)) - 1ULL;
  146. }
  147. static inline int pmbr_part_valid(gpt_mbr_record *part)
  148. {
  149. if (part->os_type != EFI_PMBR_OSTYPE_EFI_GPT)
  150. goto invalid;
  151. /* set to 0x00000001 (i.e., the LBA of the GPT Partition Header) */
  152. if (le32_to_cpu(part->starting_lba) != GPT_PRIMARY_PARTITION_TABLE_LBA)
  153. goto invalid;
  154. if (le32_to_cpu(part->start_sector) != 1UL)
  155. goto invalid;
  156. return 1;
  157. invalid:
  158. return 0;
  159. }
  160. /**
  161. * is_pmbr_valid(): test Protective MBR for validity
  162. * @mbr: pointer to a legacy mbr structure
  163. *
  164. * Description: Returns 1 if PMBR is valid, 0 otherwise.
  165. * Validity depends on two things:
  166. * 1) MSDOS signature is in the last two bytes of the MBR
  167. * 2) One partition of type 0xEE is found
  168. */
  169. static int
  170. is_pmbr_valid(legacy_mbr *mbr)
  171. {
  172. int i;
  173. if (!mbr || le16_to_cpu(mbr->signature) != MSDOS_MBR_SIGNATURE)
  174. return 0;
  175. for (i = 0; i < 4; i++)
  176. if (pmbr_part_valid(&mbr->partition_record[i]))
  177. return 1;
  178. return 0;
  179. }
  180. /**
  181. * read_lba(): Read bytes from disk, starting at given LBA
  182. * @state
  183. * @lba
  184. * @buffer
  185. * @size_t
  186. *
  187. * Description: Reads @count bytes from @state->bdev into @buffer.
  188. * Returns number of bytes read on success, 0 on error.
  189. */
  190. static size_t read_lba(struct parsed_partitions *state,
  191. u64 lba, u8 *buffer, size_t count)
  192. {
  193. size_t totalreadcount = 0;
  194. struct block_device *bdev = state->bdev;
  195. sector_t n = lba * (bdev_logical_block_size(bdev) / 512);
  196. if (!buffer || lba > last_lba(bdev))
  197. return 0;
  198. while (count) {
  199. int copied = 512;
  200. Sector sect;
  201. unsigned char *data = read_part_sector(state, n++, &sect);
  202. if (!data)
  203. break;
  204. if (copied > count)
  205. copied = count;
  206. memcpy(buffer, data, copied);
  207. put_dev_sector(sect);
  208. buffer += copied;
  209. totalreadcount +=copied;
  210. count -= copied;
  211. }
  212. return totalreadcount;
  213. }
  214. /**
  215. * alloc_read_gpt_entries(): reads partition entries from disk
  216. * @state
  217. * @gpt - GPT header
  218. *
  219. * Description: Returns ptes on success, NULL on error.
  220. * Allocates space for PTEs based on information found in @gpt.
  221. * Notes: remember to free pte when you're done!
  222. */
  223. static gpt_entry *alloc_read_gpt_entries(struct parsed_partitions *state,
  224. gpt_header *gpt)
  225. {
  226. size_t count;
  227. gpt_entry *pte;
  228. if (!gpt)
  229. return NULL;
  230. count = le32_to_cpu(gpt->num_partition_entries) *
  231. le32_to_cpu(gpt->sizeof_partition_entry);
  232. if (!count)
  233. return NULL;
  234. pte = kmalloc(count, GFP_KERNEL);
  235. if (!pte)
  236. return NULL;
  237. if (read_lba(state, le64_to_cpu(gpt->partition_entry_lba),
  238. (u8 *) pte,
  239. count) < count) {
  240. kfree(pte);
  241. pte=NULL;
  242. return NULL;
  243. }
  244. return pte;
  245. }
  246. /**
  247. * alloc_read_gpt_header(): Allocates GPT header, reads into it from disk
  248. * @state
  249. * @lba is the Logical Block Address of the partition table
  250. *
  251. * Description: returns GPT header on success, NULL on error. Allocates
  252. * and fills a GPT header starting at @ from @state->bdev.
  253. * Note: remember to free gpt when finished with it.
  254. */
  255. static gpt_header *alloc_read_gpt_header(struct parsed_partitions *state,
  256. u64 lba)
  257. {
  258. gpt_header *gpt;
  259. unsigned ssz = bdev_logical_block_size(state->bdev);
  260. gpt = kmalloc(ssz, GFP_KERNEL);
  261. if (!gpt)
  262. return NULL;
  263. if (read_lba(state, lba, (u8 *) gpt, ssz) < ssz) {
  264. kfree(gpt);
  265. gpt=NULL;
  266. return NULL;
  267. }
  268. return gpt;
  269. }
  270. /**
  271. * is_gpt_valid() - tests one GPT header and PTEs for validity
  272. * @state
  273. * @lba is the logical block address of the GPT header to test
  274. * @gpt is a GPT header ptr, filled on return.
  275. * @ptes is a PTEs ptr, filled on return.
  276. *
  277. * Description: returns 1 if valid, 0 on error.
  278. * If valid, returns pointers to newly allocated GPT header and PTEs.
  279. */
  280. static int is_gpt_valid(struct parsed_partitions *state, u64 lba,
  281. gpt_header **gpt, gpt_entry **ptes)
  282. {
  283. u32 crc, origcrc;
  284. u64 lastlba;
  285. if (!ptes)
  286. return 0;
  287. if (!(*gpt = alloc_read_gpt_header(state, lba)))
  288. return 0;
  289. /* Check the GUID Partition Table signature */
  290. if (le64_to_cpu((*gpt)->signature) != GPT_HEADER_SIGNATURE) {
  291. pr_debug("GUID Partition Table Header signature is wrong:"
  292. "%lld != %lld\n",
  293. (unsigned long long)le64_to_cpu((*gpt)->signature),
  294. (unsigned long long)GPT_HEADER_SIGNATURE);
  295. goto fail;
  296. }
  297. /* Check the GUID Partition Table header size is too big */
  298. if (le32_to_cpu((*gpt)->header_size) >
  299. bdev_logical_block_size(state->bdev)) {
  300. pr_debug("GUID Partition Table Header size is too large: %u > %u\n",
  301. le32_to_cpu((*gpt)->header_size),
  302. bdev_logical_block_size(state->bdev));
  303. goto fail;
  304. }
  305. /* Check the GUID Partition Table header size is too small */
  306. if (le32_to_cpu((*gpt)->header_size) < sizeof(gpt_header)) {
  307. pr_debug("GUID Partition Table Header size is too small: %u < %zu\n",
  308. le32_to_cpu((*gpt)->header_size),
  309. sizeof(gpt_header));
  310. goto fail;
  311. }
  312. /* Check the GUID Partition Table CRC */
  313. origcrc = le32_to_cpu((*gpt)->header_crc32);
  314. (*gpt)->header_crc32 = 0;
  315. crc = efi_crc32((const unsigned char *) (*gpt), le32_to_cpu((*gpt)->header_size));
  316. if (crc != origcrc) {
  317. pr_debug("GUID Partition Table Header CRC is wrong: %x != %x\n",
  318. crc, origcrc);
  319. goto fail;
  320. }
  321. (*gpt)->header_crc32 = cpu_to_le32(origcrc);
  322. /* Check that the my_lba entry points to the LBA that contains
  323. * the GUID Partition Table */
  324. if (le64_to_cpu((*gpt)->my_lba) != lba) {
  325. pr_debug("GPT my_lba incorrect: %lld != %lld\n",
  326. (unsigned long long)le64_to_cpu((*gpt)->my_lba),
  327. (unsigned long long)lba);
  328. goto fail;
  329. }
  330. /* Check the first_usable_lba and last_usable_lba are
  331. * within the disk.
  332. */
  333. lastlba = last_lba(state->bdev);
  334. if (le64_to_cpu((*gpt)->first_usable_lba) > lastlba) {
  335. pr_debug("GPT: first_usable_lba incorrect: %lld > %lld\n",
  336. (unsigned long long)le64_to_cpu((*gpt)->first_usable_lba),
  337. (unsigned long long)lastlba);
  338. goto fail;
  339. }
  340. if (le64_to_cpu((*gpt)->last_usable_lba) > lastlba) {
  341. pr_debug("GPT: last_usable_lba incorrect: %lld > %lld\n",
  342. (unsigned long long)le64_to_cpu((*gpt)->last_usable_lba),
  343. (unsigned long long)lastlba);
  344. goto fail;
  345. }
  346. /* Check that sizeof_partition_entry has the correct value */
  347. if (le32_to_cpu((*gpt)->sizeof_partition_entry) != sizeof(gpt_entry)) {
  348. pr_debug("GUID Partitition Entry Size check failed.\n");
  349. goto fail;
  350. }
  351. if (!(*ptes = alloc_read_gpt_entries(state, *gpt)))
  352. goto fail;
  353. /* Check the GUID Partition Entry Array CRC */
  354. crc = efi_crc32((const unsigned char *) (*ptes),
  355. le32_to_cpu((*gpt)->num_partition_entries) *
  356. le32_to_cpu((*gpt)->sizeof_partition_entry));
  357. if (crc != le32_to_cpu((*gpt)->partition_entry_array_crc32)) {
  358. pr_debug("GUID Partitition Entry Array CRC check failed.\n");
  359. goto fail_ptes;
  360. }
  361. /* We're done, all's well */
  362. return 1;
  363. fail_ptes:
  364. kfree(*ptes);
  365. *ptes = NULL;
  366. fail:
  367. kfree(*gpt);
  368. *gpt = NULL;
  369. return 0;
  370. }
  371. /**
  372. * is_pte_valid() - tests one PTE for validity
  373. * @pte is the pte to check
  374. * @lastlba is last lba of the disk
  375. *
  376. * Description: returns 1 if valid, 0 on error.
  377. */
  378. static inline int
  379. is_pte_valid(const gpt_entry *pte, const u64 lastlba)
  380. {
  381. if ((!efi_guidcmp(pte->partition_type_guid, NULL_GUID)) ||
  382. le64_to_cpu(pte->starting_lba) > lastlba ||
  383. le64_to_cpu(pte->ending_lba) > lastlba)
  384. return 0;
  385. return 1;
  386. }
  387. /**
  388. * compare_gpts() - Search disk for valid GPT headers and PTEs
  389. * @pgpt is the primary GPT header
  390. * @agpt is the alternate GPT header
  391. * @lastlba is the last LBA number
  392. * Description: Returns nothing. Sanity checks pgpt and agpt fields
  393. * and prints warnings on discrepancies.
  394. *
  395. */
  396. static void
  397. compare_gpts(gpt_header *pgpt, gpt_header *agpt, u64 lastlba)
  398. {
  399. int error_found = 0;
  400. if (!pgpt || !agpt)
  401. return;
  402. if (le64_to_cpu(pgpt->my_lba) != le64_to_cpu(agpt->alternate_lba)) {
  403. printk(KERN_WARNING
  404. "GPT:Primary header LBA != Alt. header alternate_lba\n");
  405. printk(KERN_WARNING "GPT:%lld != %lld\n",
  406. (unsigned long long)le64_to_cpu(pgpt->my_lba),
  407. (unsigned long long)le64_to_cpu(agpt->alternate_lba));
  408. error_found++;
  409. }
  410. if (le64_to_cpu(pgpt->alternate_lba) != le64_to_cpu(agpt->my_lba)) {
  411. printk(KERN_WARNING
  412. "GPT:Primary header alternate_lba != Alt. header my_lba\n");
  413. printk(KERN_WARNING "GPT:%lld != %lld\n",
  414. (unsigned long long)le64_to_cpu(pgpt->alternate_lba),
  415. (unsigned long long)le64_to_cpu(agpt->my_lba));
  416. error_found++;
  417. }
  418. if (le64_to_cpu(pgpt->first_usable_lba) !=
  419. le64_to_cpu(agpt->first_usable_lba)) {
  420. printk(KERN_WARNING "GPT:first_usable_lbas don't match.\n");
  421. printk(KERN_WARNING "GPT:%lld != %lld\n",
  422. (unsigned long long)le64_to_cpu(pgpt->first_usable_lba),
  423. (unsigned long long)le64_to_cpu(agpt->first_usable_lba));
  424. error_found++;
  425. }
  426. if (le64_to_cpu(pgpt->last_usable_lba) !=
  427. le64_to_cpu(agpt->last_usable_lba)) {
  428. printk(KERN_WARNING "GPT:last_usable_lbas don't match.\n");
  429. printk(KERN_WARNING "GPT:%lld != %lld\n",
  430. (unsigned long long)le64_to_cpu(pgpt->last_usable_lba),
  431. (unsigned long long)le64_to_cpu(agpt->last_usable_lba));
  432. error_found++;
  433. }
  434. if (efi_guidcmp(pgpt->disk_guid, agpt->disk_guid)) {
  435. printk(KERN_WARNING "GPT:disk_guids don't match.\n");
  436. error_found++;
  437. }
  438. if (le32_to_cpu(pgpt->num_partition_entries) !=
  439. le32_to_cpu(agpt->num_partition_entries)) {
  440. printk(KERN_WARNING "GPT:num_partition_entries don't match: "
  441. "0x%x != 0x%x\n",
  442. le32_to_cpu(pgpt->num_partition_entries),
  443. le32_to_cpu(agpt->num_partition_entries));
  444. error_found++;
  445. }
  446. if (le32_to_cpu(pgpt->sizeof_partition_entry) !=
  447. le32_to_cpu(agpt->sizeof_partition_entry)) {
  448. printk(KERN_WARNING
  449. "GPT:sizeof_partition_entry values don't match: "
  450. "0x%x != 0x%x\n",
  451. le32_to_cpu(pgpt->sizeof_partition_entry),
  452. le32_to_cpu(agpt->sizeof_partition_entry));
  453. error_found++;
  454. }
  455. if (le32_to_cpu(pgpt->partition_entry_array_crc32) !=
  456. le32_to_cpu(agpt->partition_entry_array_crc32)) {
  457. printk(KERN_WARNING
  458. "GPT:partition_entry_array_crc32 values don't match: "
  459. "0x%x != 0x%x\n",
  460. le32_to_cpu(pgpt->partition_entry_array_crc32),
  461. le32_to_cpu(agpt->partition_entry_array_crc32));
  462. error_found++;
  463. }
  464. if (le64_to_cpu(pgpt->alternate_lba) != lastlba) {
  465. printk(KERN_WARNING
  466. "GPT:Primary header thinks Alt. header is not at the end of the disk.\n");
  467. printk(KERN_WARNING "GPT:%lld != %lld\n",
  468. (unsigned long long)le64_to_cpu(pgpt->alternate_lba),
  469. (unsigned long long)lastlba);
  470. error_found++;
  471. }
  472. if (le64_to_cpu(agpt->my_lba) != lastlba) {
  473. printk(KERN_WARNING
  474. "GPT:Alternate GPT header not at the end of the disk.\n");
  475. printk(KERN_WARNING "GPT:%lld != %lld\n",
  476. (unsigned long long)le64_to_cpu(agpt->my_lba),
  477. (unsigned long long)lastlba);
  478. error_found++;
  479. }
  480. if (error_found)
  481. printk(KERN_WARNING
  482. "GPT: Use GNU Parted to correct GPT errors.\n");
  483. return;
  484. }
  485. /**
  486. * find_valid_gpt() - Search disk for valid GPT headers and PTEs
  487. * @state
  488. * @gpt is a GPT header ptr, filled on return.
  489. * @ptes is a PTEs ptr, filled on return.
  490. * Description: Returns 1 if valid, 0 on error.
  491. * If valid, returns pointers to newly allocated GPT header and PTEs.
  492. * Validity depends on PMBR being valid (or being overridden by the
  493. * 'gpt' kernel command line option) and finding either the Primary
  494. * GPT header and PTEs valid, or the Alternate GPT header and PTEs
  495. * valid. If the Primary GPT header is not valid, the Alternate GPT header
  496. * is not checked unless the 'gpt' kernel command line option is passed.
  497. * This protects against devices which misreport their size, and forces
  498. * the user to decide to use the Alternate GPT.
  499. */
  500. static int find_valid_gpt(struct parsed_partitions *state, gpt_header **gpt,
  501. gpt_entry **ptes)
  502. {
  503. int good_pgpt = 0, good_agpt = 0, good_pmbr = 0;
  504. gpt_header *pgpt = NULL, *agpt = NULL;
  505. gpt_entry *pptes = NULL, *aptes = NULL;
  506. legacy_mbr *legacymbr;
  507. u64 lastlba;
  508. if (!ptes)
  509. return 0;
  510. lastlba = last_lba(state->bdev);
  511. if (!force_gpt) {
  512. /* This will be added to the EFI Spec. per Intel after v1.02. */
  513. legacymbr = kzalloc(sizeof (*legacymbr), GFP_KERNEL);
  514. if (legacymbr) {
  515. read_lba(state, 0, (u8 *) legacymbr,
  516. sizeof (*legacymbr));
  517. good_pmbr = is_pmbr_valid(legacymbr);
  518. kfree(legacymbr);
  519. }
  520. if (!good_pmbr)
  521. goto fail;
  522. }
  523. good_pgpt = is_gpt_valid(state, GPT_PRIMARY_PARTITION_TABLE_LBA,
  524. &pgpt, &pptes);
  525. if (good_pgpt)
  526. good_agpt = is_gpt_valid(state,
  527. le64_to_cpu(pgpt->alternate_lba),
  528. &agpt, &aptes);
  529. if (!good_agpt && force_gpt)
  530. good_agpt = is_gpt_valid(state, lastlba, &agpt, &aptes);
  531. /* The obviously unsuccessful case */
  532. if (!good_pgpt && !good_agpt)
  533. goto fail;
  534. compare_gpts(pgpt, agpt, lastlba);
  535. /* The good cases */
  536. if (good_pgpt) {
  537. *gpt = pgpt;
  538. *ptes = pptes;
  539. kfree(agpt);
  540. kfree(aptes);
  541. if (!good_agpt) {
  542. printk(KERN_WARNING
  543. "Alternate GPT is invalid, "
  544. "using primary GPT.\n");
  545. }
  546. return 1;
  547. }
  548. else if (good_agpt) {
  549. *gpt = agpt;
  550. *ptes = aptes;
  551. kfree(pgpt);
  552. kfree(pptes);
  553. printk(KERN_WARNING
  554. "Primary GPT is invalid, using alternate GPT.\n");
  555. return 1;
  556. }
  557. fail:
  558. kfree(pgpt);
  559. kfree(agpt);
  560. kfree(pptes);
  561. kfree(aptes);
  562. *gpt = NULL;
  563. *ptes = NULL;
  564. return 0;
  565. }
  566. /**
  567. * efi_partition(struct parsed_partitions *state)
  568. * @state
  569. *
  570. * Description: called from check.c, if the disk contains GPT
  571. * partitions, sets up partition entries in the kernel.
  572. *
  573. * If the first block on the disk is a legacy MBR,
  574. * it will get handled by msdos_partition().
  575. * If it's a Protective MBR, we'll handle it here.
  576. *
  577. * We do not create a Linux partition for GPT, but
  578. * only for the actual data partitions.
  579. * Returns:
  580. * -1 if unable to read the partition table
  581. * 0 if this isn't our partition table
  582. * 1 if successful
  583. *
  584. */
  585. int efi_partition(struct parsed_partitions *state)
  586. {
  587. gpt_header *gpt = NULL;
  588. gpt_entry *ptes = NULL;
  589. u32 i;
  590. unsigned ssz = bdev_logical_block_size(state->bdev) / 512;
  591. if (!find_valid_gpt(state, &gpt, &ptes) || !gpt || !ptes) {
  592. kfree(gpt);
  593. kfree(ptes);
  594. return 0;
  595. }
  596. pr_debug("GUID Partition Table is valid! Yea!\n");
  597. for (i = 0; i < le32_to_cpu(gpt->num_partition_entries) && i < state->limit-1; i++) {
  598. struct partition_meta_info *info;
  599. unsigned label_count = 0;
  600. unsigned label_max;
  601. u64 start = le64_to_cpu(ptes[i].starting_lba);
  602. u64 size = le64_to_cpu(ptes[i].ending_lba) -
  603. le64_to_cpu(ptes[i].starting_lba) + 1ULL;
  604. if (!is_pte_valid(&ptes[i], last_lba(state->bdev)))
  605. continue;
  606. put_partition(state, i+1, start * ssz, size * ssz);
  607. /* If this is a RAID volume, tell md */
  608. if (!efi_guidcmp(ptes[i].partition_type_guid,
  609. PARTITION_LINUX_RAID_GUID))
  610. state->parts[i + 1].flags = ADDPART_FLAG_RAID;
  611. info = &state->parts[i + 1].info;
  612. efi_guid_unparse(&ptes[i].unique_partition_guid, info->uuid);
  613. /* Naively convert UTF16-LE to 7 bits. */
  614. label_max = min(sizeof(info->volname) - 1,
  615. sizeof(ptes[i].partition_name));
  616. info->volname[label_max] = 0;
  617. while (label_count < label_max) {
  618. u8 c = ptes[i].partition_name[label_count] & 0xff;
  619. if (c && !isprint(c))
  620. c = '!';
  621. info->volname[label_count] = c;
  622. label_count++;
  623. }
  624. state->parts[i + 1].has_info = true;
  625. }
  626. kfree(ptes);
  627. kfree(gpt);
  628. strlcat(state->pp_buf, "\n", PAGE_SIZE);
  629. return 1;
  630. }